Service frequency ranges are getting extended in the recent communication networks and radiuses of cells are gradually decreased for supporting (covering) high-speed communication and more traffic. Thus, many problems may be caused in view of applying the conventional centralized cellular radio network as it is even later. That is, since a position of the base station is fixed, flexibility of a radio link configuration is low. As a result, it has been difficult to efficiently provide communication services in a radio (wireless) environment where there is a rapid change in traffic distribution and call demands.
To address such problems, a relay, more particularly, a multi-hop relay has been considered in the next generation wireless communication system, called as Long Term Evolution Advanced (LTE-A) system or an Evolved Universal Terrestrial Radio Access (E-UTRA) system. The relay system can broaden cell service coverage by covering a partial shadow area generated within a cell region, increase system capacity, and reduce an initial installation charge since a relay (hereinafter, referred to as ‘relay station (RS)’) is established in an initial stage when a service request is not frequently made.
In the relay system, a source node may transmit multiple data streams to relay nodes and a destination node using a superposition coding. Upon reception of the multiple data streams from the source node, the relay node may decode the data streams and re-encode the decoded data streams so as to perform a collaborative data transmission to the destination node. The collaborative communication method can enhance efficiency of data transmission and improve throughput of an entire network as well as compensating for resource consumption of each node.
However, interference may be caused between the multiple data streams transmitted from the source node and the relay node depending on channel environments. Under this state, the destination node may be unable to normally decode multiple data streams.